Fire and Rescue NSW, as well as NSW Rural Fire Service personnel were initially called out to the emergency on Lindfield Park Road at 12.06pm on July 19.

Overnight the fire made its way from bushland near Port Macquarie Driving Range and Mini Golf to Port Macquarie Airport.

Fire and Rescue NSW Port Macquarie station commander Gavin Muller said the bus fire now covers about 40 hectares.

"Fire and Rescue, Rural Fire Service staff are working to control the area today, however the western edge of the fire is uncontained," said Mr Muller.

"There is minimal access due to terrain in the area including swamp areas, in some cases the fire is burning on water grasses.

"We are anticipating there will be smoke over the weekend and are asking residents if they don't need to leave, to stay off roads and monitor the Fires Near Me app.

"We are considering putting tactical back burns in."

Mr Muller said there are no properties currently under threat and residents are encouraged to only ring 000 if there is immediate danger due to a large number of calls being received.

The cause and original of the fire are currently under investigation.

The nearby Oxley Highway was closed in both directions due to smoke until earlier today (July 19), it has since been reopened.

North Coast Public Health Unit director Paul Corben said the Unit is advising people to consider their health while smoke is affecting the area.

"Fine smoke particles are known to affect the human breathing system. The smaller or finer the particles, the deeper they go into the lungs," said Mr Corben.

"These particles can cause a variety of health problems, such as itchy or burning eyes, throat irritation, runny nose and illnesses such as bronchitis.

"The smoke particles can also aggravate existing lung conditions such as chronic bronchitis, emphysema and asthma.

"Smoke particle levels are likely to be higher outdoors than indoors, so people sensitive to fine particles should limit the time they spend outside.

"People with asthma and other lung conditions should not engage in vigorous exercise and, if possible, they should stay in air-conditioned premises where filtration systems can help to reduce smoke particles in the air.

"Healthy adults may also feel the effects of fine particles that can irritate the lungs, so it's wise to reschedule or cut back on prolonged or strenuous outdoor activities when smoke levels are high."

To stay up to date with the situation, please download the Fires Near Me App, or visit www.rfs.nsw.gov.au

Remember, now is the time to start thinking about preparing your property for the summer ahead. Go to www.myfireplan.com.au

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